Brown spot disease is the main disease of chrysanthemum, and the damaged plants often have the appearance of coking and shedding of leaves, and lightly affect the normal growth and flowering quality of plants, while the whole plant is dead. In addition to harming chrysanthemums, this disease also harms various asteraceae plants such as chamomile and pyrethrum. Brown spot mainly damages the leaves of chrysanthemum. The disease gradually developed from the lower leaves of the plant to the upper part. At the beginning of the disease, pale yellow and purple-brown spots of varying sizes appeared on the leaves and then expanded into round, oval or irregular lesions. The edge of the lesion is dark brown, with a clear boundary with healthy parts. The central part is gray-brown. Less obvious black spots are pathogenic bacteria on the later lesions. When the disease is severe, the lesions are connected to each other to make the entire leaf yellow, and then turn black, and then scorch. The diseased leaves that are black and dry are sometimes rolled into a tube and hung on the stem, and do not dry out. Brown spot is a fungal disease. When the temperature is appropriate in the spring of the following year, the pathogen is transmitted by wind and rain. It can be affected every year from April to October, but the incidence is the heaviest in autumn. Especially after the rain, the condition developed rapidly. To control brown spot, we need to start from the following aspects: 1. Strengthen cultivation management. To plant chrysanthemums in rotation should be rotated down to avoid continuous cropping. Potted chrysanthemums should be replaced with new culture soils every year. Watering should be appropriate, sunny days should be more watering, cloudy days less watering, attention to drainage after the rain. Fertilization should be reasonable, increase phosphorus, potash fertilizer, promote robust growth of plants, improve disease resistance. The plants should not be planted too densely, and it is necessary to ensure ventilation and light transmission between the plants. 2. Select mother plant strains with strong disease resistance for cutting and cutting. 3. In the late fall and early winter period, diseased leaves and diseased plant residues should be promptly eliminated, and centrally destroyed and buried to eliminate the source of infection. 4. Chemical control. In the early stage of onset, spray 70% mancozeb WP 500 times and 75% chlorothalonil wettable powder 600 times once a week for 4-5 times. During the onset, spray 80% Captoptan WP 500 times, or mix 50% thiophanate-methyl 1000 times and 80% Captan-500%, or use 45% chlorothalonil and carbendazim Mixing the suspension 1000 times liquid suspension can achieve control effect. 8 Inch Biometric Tablet,Industrial Rugged Android Tablet,Portable Fingerprint Tablet,Rugged Portable Time Attendance Tablet Chongqing Huifan Technology Co., Ltd , https://www.hfsecuritytech.com